The present teachings are predicated upon providing an improved brake rotor with increased cooling and a reduced unsprung mass. For example, the rotor may be used with almost any vehicle (e.g. car, truck, bus, train, airplane, or the like). Alternatively, the rotor may be integrated into assemblies used for manufacturing or other equipment that require a brake such as a lathe, wind turbine, winder for paper products or cloth, amusement park rides, or the like. However, the present teachings are most suitable for use with a vehicle (i.e. a car, truck, sports utility vehicle, or the like).
Generally, a braking system includes a rotor, a caliper body, a support bracket, an inboard brake pad, and an outboard brake pad that are on opposing sides of the rotor. The caliper body includes a bridge, one or more fingers, and a piston bore. Typically, braking systems include one or more pin bores on the caliper body, brake pads, and support bracket for receiving a pin that secures the caliper and the brake pads on the support bracket so that the brake pads can slide on the pins to create a braking force. The brake pads are moved by a piston located in the piston bore. The piston bore further includes a fluid inlet in a closed wall, a front opening, and a cylindrical side wall that includes a seal groove located near the front opening. The brake fluid enters the closed wall of the piston bore during a pressure apply and moves the piston towards the front opening into contact with a brake pad. The brake pad slides towards the rotor and simultaneously or slightly thereafter the one or more fingers push the opposing brake pad towards and into contact the opposing side of the rotor. The contact between the inboard brake pad, the outboard brake pad, and the rotor create a friction force that reduces the rotational speed of the rotor, thus, slowing and/or stopping the article attached to the braking system. The friction force between the brake pads and the rotor during normal braking operation causes the brake pads, the rotor, or both, to become heated. During extended braking and/or high intensity braking the brake pads, the rotor, or both may become excessively heated. This heat, if not dissipated may heat the brake fluid; damage (e.g., crack, warp, or both) the brake pads, the rotor, or both; cause the brake system to have a reduced braking capacity or even fail so that the braking system does not adequately brake; or a combination thereof.
Additionally, the creation of unitary rotors with improved heat dissipation has been limited due to manufacturing constraints and concern that some methods for providing for dissipation of heat may negatively impact the structural strength of the rotor. Venting locations and configurations have generally been limited to a single plane. Examples of some rotors and attempts to dissipate heat of rotors and/or brake pads may be found in U.S. Pat. Nos. 4,757,883; 5,915,747; 6,216,828; and 7,066,306 U.S. Patent Application Publication No. 2007/0181390; International Patent Application No. WO2009129231; and German Patent No. DE3924849 all of which are incorporated by reference herein for all purposes.
It would be attractive to have a vented rotor that has an increased heat dissipation capacity while maintaining structural integrity and resistance to failure. It would further be attractive to have a rotor that dissipates heat quickly so that heat is not transferred from the brake pads and/or rotor into the brake fluid. What is needed is a rotor with a reduced unsprung mass, when compared to standard rotors, which has increased cooling capabilities. What is further needed is a method of manufacturing an improved rotor that includes the improved heat dissipation structures as described herein while maintaining the necessary strength of the rotor.